Linear Transformation from R3 to R3

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A linear transformation T from R3 to R3 can be defined by its action on a basis, as shown in the discussion. The transformation maps the standard basis vectors to specific vectors, creating a range spanned by (1, 0, -1) and (1, 2, 2). The proposed matrices demonstrate valid representations of this transformation, indicating that different configurations can still satisfy the transformation's requirements. The discussion also suggests that using double columns of (1, 2, 2) could fulfill the transformation criteria. This highlights the flexibility in defining linear transformations while maintaining the same range.
jolly_math
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Homework Statement
Describe explicitly a linear transformation from R3 into R3 which has as its
range the subspace spanned by (1, 0, -1) and (1, 2, 2).
Relevant Equations
linear transformation
"There is a linear transformation T from R3 to R3 such that T (1, 0, 0) = (1,0,−1), T(0,1,0) = (1,0,−1) and T(0,0,1) = (1,2,2)" - why is this the case?

Thank you.
 
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Does it help to glance at the following matrices:
$$
\begin{bmatrix}
1 & 1 & 1 \\
0 & 0 & 2 \\
-1 & -1 & 2\\
\end{bmatrix}
\times
\begin{bmatrix}
x \\
y \\
z\\
\end{bmatrix}
$$
?
 
jolly_math said:
Homework Statement:: Describe explicitly a linear transformation from R3 into R3 which has as its
range the subspace spanned by (1, 0, -1) and (1, 2, 2).
Relevant Equations:: linear transformation

"There is a linear transformation T from R3 to R3 such that T (1, 0, 0) = (1,0,−1), T(0,1,0) = (1,0,−1) and T(0,0,1) = (1,2,2)" - why is this the case?

Thank you.
A linear transformation can be fully described by its action on any basis. Can you see why?
 
Hall said:
$$
\begin{bmatrix}
1 & 1 & 1 \\
0 & 0 & 2 \\
-1 & -1 & 2\\
\end{bmatrix}
\times
\begin{bmatrix}
x \\
y \\
z\\
\end{bmatrix}
$$

For R3, would
$$
\begin{bmatrix}
1 & 1 & 1 \\
0 & 2 & 0 \\
-1 & 2 & -1\\
\end{bmatrix}
\times
\begin{bmatrix}
x \\
y \\
z\\
\end{bmatrix}
$$
also work (switching which vector corresponds to each basis)? Thanks.
 
jolly_math said:
For R3, would
$$
\begin{bmatrix}
1 & 1 & 1 \\
0 & 2 & 0 \\
-1 & 2 & -1\\
\end{bmatrix}
\times
\begin{bmatrix}
x \\
y \\
z\\
\end{bmatrix}
$$
also work (switching which vector corresponds to each basis)? Thanks.
Yes, I think. I think even double columns of ##(1,2,2)## will also satisfy the given things.
 
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